Crystallization Kinetics Control Enabled by a Green Ionic Liquid Additive toward Efficient and Stable Carbon-Based...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Carbon-based mesoscopic perovskite solar cells (MPSCs) offer a cost-effective and stable photovoltaic technology.
• Improving the efficiency and longevity of MPSCs is crucial for their widespread adoption.

Purpose of the Study:

• To investigate the effect of methylammonium acetate (MAAc) as an ionic liquid additive in methylammonium lead triiodide (MAPbI3) based MPSCs.
• To enhance the performance and stability of MPSCs through controlled perovskite crystallization.

Main Methods:

• Incorporation of methylammonium acetate (MAAc) into the methylammonium lead triiodide (MAPbI3) perovskite precursor.
• Fabrication of carbon-based mesoscopic perovskite solar cells (MPSCs) using the MAAc-modified perovskite.
• Characterization of perovskite film properties, including crystallinity, defect density, and morphology.
• Performance testing of MPSCs to determine power conversion efficiency (PCE) and stability.

Main Results:

• MAAc preferentially interacts with PbI2, forming an intermediate phase that controls MAPbI3 crystallization.
• MAAc-treated perovskite films exhibit improved crystallinity, reduced defect density, and denser pore filling.
• Optimized MAAc-engineered MPSCs achieved a champion power conversion efficiency (PCE) of 13.54%, a 24% increase over control devices.
• Unencapsulated MAAc-engineered MPSCs retained 90% of their initial PCE after 50 days of storage, demonstrating enhanced air stability.

Conclusions:

• Methylammonium acetate (MAAc) is an effective additive for improving the efficiency and stability of carbon-based mesoscopic perovskite solar cells (MPSCs).
• The MAAc-induced control over perovskite crystallization significantly reduces carrier recombination losses.
• This study presents a viable strategy for developing high-performance, stable, and eco-friendly perovskite solar cells.